[Yashwanth Reddy Verupaka (yashwanth195)]

Summary

Allow Heft plugins to declare parameters incompatible with cleaning or watch mode. Reject those combinations before lifecycle hooks, plugin application, output deletion, or watch startup.

Details

• Add optional allowWithClean and allowInWatchMode metadata to all seven plugin parameter kinds.
• Validate parsed effective values, including configured defaults, scoped names, short names, and alias defaults. True flags, nonempty lists, and defined scalars are active, including 0 and empty strings.
• Restrictions are opt-in: omitted or true metadata preserves existing behavior, as does the standalone clean command. Validation runs once before action startup.

This is a standalone change based directly on main. It contains no plugin-selection or sharding changes and requires no other PR. The build produced no public API report changes.

The CI follow-up also replaces a timing-dependent daemon test with the existing deferred-write integration-test pattern and a fake-timer unit regression. This checks write-completion ordering and idle-to-active tracking without relying on real-time deadlines or socket buffer sizes; daemon production code is unchanged.

How it was tested

Windows, Node.js 24.22.1, repository Rush 5.182.0. All checks used this branch's own build outputs.

Command	Result
node common\scripts\install-run-rush.js build --to @rushstack/heft	Passed: 17 successful operations, 2 no-ops; includes TypeScript, lint, and API extraction.
From apps\heft: node ..\..\common\scripts\install-run-rushx.js _phase:test --test-path-pattern Parameter --disable-code-coverage	Passed: 2 suites, 78 tests.
node common\scripts\install-run-rush.js build --to @rushstack/rush-daemon	Passed: 28 successful operations, 17 restored from cache, 4 no-ops; includes TypeScript, lint, and API extraction.
From libraries\rush-daemon: node ..\..\common\scripts\install-run-rushx.js _phase:test --find-related-tests lib-commonjs\test\ConnectingClientTracker.test.js --find-related-tests lib-commonjs\test\DaemonRequestWirePhased.test.js --disable-code-coverage	Passed: 2 suites, 18 tests.
node common\scripts\install-run-rush.js prettier	Passed on the scoped staged changes.
node common\scripts\install-run-rush.js change --verify --target-branch upstream/main	Passed.
git diff --cached --check and git diff --check	Passed.

The 68 parameter-manager tests cover every parameter kind, schema validation, inactive values, independent clean/watch restrictions, defaults, aliases, and scoped collisions. The 10 CLI tests launch the built Heft executable and verify preserved output sentinels, absent lifecycle/task markers, and immediate watch rejection, plus successful normal cleaning and unrestricted execution.

For the daemon follow-up, all 10 tracker unit tests and 8 phased-request wire integration tests passed. The new cases assert the delayed send completes before the daemon refreshes activity, and use fake timers to verify the idle-to-active transition. Existing Heft validation was reused rather than rerunning unchanged suites.

Impacted documentation

The schema descriptions and TypeScript metadata documentation explain the opt-in behavior and effective-value rules. No heft-plugin.json init template exists in this repository. The CLI documentation can mention the preflight behavior: https://heft.rushstack.io/pages/intro/cli/